1. Field of the Invention
The present invention deals with the general field of separation of components utilizing chromatographic columns wherein various solid materials are placed within the columns to detain components of a moving mixture to different degrees so that they will become separated during passage through the column. Basically, such separation always is possible within a column containing the given solid absorbent whenever one component has a rate of passage that is significantly different from that of another component. In theory, any two such components can be separated given a long enough column. The present invention provides a novel convenient way to form and use such packed columns of any desirable length within practical space limitations, and also provides two novel processes and approaches whereby continuous separation of volatile mixtures can be performed.
2. Description of the Prior Art
Devices in the prior art have been patented such as U.S. Pat. No. 1,985,104; 2,882,244; 2,913,501; 2,965,680, 3,366,582; 3,408,267; and 3,766,660.
The formation of chromatographic columns having a solid absorbent enclosed in a conduit is old in the art. Normally, when such processes have utilized solid polymeric packing material it has been in the form of granules or pellets. When fibrous packing was used, the fibers have been packed isotropically as individual elements in the same manner as other granular material. For example, when textile yarns were the source of the packing material, they were first chopped into small discrete pieces. Whatever the nature of the individual packing elements, it has always been necessary to take pains that the packing was uniform across and through the column, which necessitated slow and careful filling procedures and limited the practical length of column which could be used without excessive resistance to flow. The present invention provides a means for much more easily packing such columns by using continuous yarns which permits the use of columns of much greater length than hitherto possible.
Heretofore the main problem with the use of such systems for continuous separation of mixtures has been the removal of the adsorbed component from the column quickly enough so that it will not interfere with the separation of the next mixture charge. If this cannot be done the column packing will soon become saturated and will not perform its separating function. The present invention teaches that certain types of continuous polymeric materials and continuous fibrous textile solids that do not irreversibly adsorb volatiles can be made to retard the passage of certain species to a greater or lesser degree depending on certain controllable variables, e.g., temperature. This effect plus the use of two novel mechanical arrangements have been used to quickly regenerate such columns so that they will be available to receive and process an unlimited series of charges of feed mixture.